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In late 2003, researchers at Advanced Cell Technology, a small biotech startup in Worcester, MA, thought they were about to do something remarkable. They had painstakingly generated cloned human embryos from adult cells and were trying to keep them alive long enough to harvest their inner cell masses, precious balls of cells that give rise to stem cells.

It was one of the most sought-after prizes of biomedical research: a way to grow embryonic stem cells directly from, say, a skin cell taken from a specific patient. It was also one of biomedicine’s most speculative projects; indeed, the scientists at Advanced Cell Technology (ACT) were the only team in the United States actively pursuing it. But Robert Lanza (see “Stem Cell Hope”), who headed the group, says he believes that his team at ACT was on the verge of success. If he’s right, and if the work had continued, the company would almost certainly have had in its hands the key to a revolutionary new set of biomedical tools – and possibly to new treatments for a host of different diseases.

But in February 2004, the ACT scientists’ hopes were dashed. A South Korean stem cell scientist named Hwang Woo Suk of Seoul National University and his colleagues announced in the journal Science that they had created patient-specific stem cells. The achievement vaulted Hwang to scientific stardom. His country named him its “supreme scientist” and honored him with a postage stamp depicting a paralyzed man able to walk again. Patients clamored to be part of his work. Hwang embraced his role as an international stem cell celebrity, announcing plans to create something called the World Stem Cell Hub, where members of his lab would clone and culture stem cell lines for scientists around the globe.

“What had been a terribly risky field that many scientists were loath to venture into now became a possibility,” says Evan Snyder, director of the Stem Cells and Regeneration Program at the Burnham Institute for Medical Research in La Jolla, CA. Many U.S. researchers who had been unable or unwilling to start cloning work themselves began planning collaborations with the Korean scientists. “We knew [cloning] would take a lot of time and money, and the Korean government was willing to throw so much at this one problem,” says Snyder. “When that seemed to have been accomplished, many of us said, Well, that’s a relief. Now we can do the real science experiments.”

However, Lanza and his colleagues, who had been so close to cloning stem cells, watched dejectedly. “It was embarrassing,” says Lanza. “This obscure group announced they had done it.” ACT was already on shaky financial ground, but Hwang’s achievement made its situation even more precarious. The company also abruptly lost its supply of human eggs – a crucial ingredient in cloning research – because clinics that ran donor programs felt no further need to participate in research whose central goal had been achieved. As a result, the scientists literally had to put their work on ice. “We had to freeze down lots of our cells. It shut down that research, and there has been no active research since,” says Lanza. There was, plainly, no glory – or profits – in coming in second.